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2012-10-31mm: fix XFS oops due to dirty pages without buffers on s390Jan Kara
commit ef5d437f71afdf4afdbab99213add99f4b1318fd upstream. On s390 any write to a page (even from kernel itself) sets architecture specific page dirty bit. Thus when a page is written to via buffered write, HW dirty bit gets set and when we later map and unmap the page, page_remove_rmap() finds the dirty bit and calls set_page_dirty(). Dirtying of a page which shouldn't be dirty can cause all sorts of problems to filesystems. The bug we observed in practice is that buffers from the page get freed, so when the page gets later marked as dirty and writeback writes it, XFS crashes due to an assertion BUG_ON(!PagePrivate(page)) in page_buffers() called from xfs_count_page_state(). Similar problem can also happen when zero_user_segment() call from xfs_vm_writepage() (or block_write_full_page() for that matter) set the hardware dirty bit during writeback, later buffers get freed, and then page unmapped. Fix the issue by ignoring s390 HW dirty bit for page cache pages of mappings with mapping_cap_account_dirty(). This is safe because for such mappings when a page gets marked as writeable in PTE it is also marked dirty in do_wp_page() or do_page_fault(). When the dirty bit is cleared by clear_page_dirty_for_io(), the page gets writeprotected in page_mkclean(). So pagecache page is writeable if and only if it is dirty. Thanks to Hugh Dickins for pointing out mapping has to have mapping_cap_account_dirty() for things to work and proposing a cleaned up variant of the patch. The patch has survived about two hours of running fsx-linux on tmpfs while heavily swapping and several days of running on out build machines where the original problem was triggered. Signed-off-by: Jan Kara <jack@suse.cz> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Hugh Dickins <hughd@google.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-31x86, mm: Trim memory in memblock to be page alignedYinghai Lu
commit 6ede1fd3cb404c0016de6ac529df46d561bd558b upstream. We will not map partial pages, so need to make sure memblock allocation will not allocate those bytes out. Also we will use for_each_mem_pfn_range() to loop to map memory range to keep them consistent. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Link: http://lkml.kernel.org/r/CAE9FiQVZirvaBMFYRfXMmWEcHbKSicQEHz4VAwUv0xFCk51ZNw@mail.gmail.com Acked-by: Jacob Shin <jacob.shin@amd.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-21tmpfs,ceph,gfs2,isofs,reiserfs,xfs: fix fh_len checkingHugh Dickins
commit 35c2a7f4908d404c9124c2efc6ada4640ca4d5d5 upstream. Fuzzing with trinity oopsed on the 1st instruction of shmem_fh_to_dentry(), u64 inum = fid->raw[2]; which is unhelpfully reported as at the end of shmem_alloc_inode(): BUG: unable to handle kernel paging request at ffff880061cd3000 IP: [<ffffffff812190d0>] shmem_alloc_inode+0x40/0x40 Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC Call Trace: [<ffffffff81488649>] ? exportfs_decode_fh+0x79/0x2d0 [<ffffffff812d77c3>] do_handle_open+0x163/0x2c0 [<ffffffff812d792c>] sys_open_by_handle_at+0xc/0x10 [<ffffffff83a5f3f8>] tracesys+0xe1/0xe6 Right, tmpfs is being stupid to access fid->raw[2] before validating that fh_len includes it: the buffer kmalloc'ed by do_sys_name_to_handle() may fall at the end of a page, and the next page not be present. But some other filesystems (ceph, gfs2, isofs, reiserfs, xfs) are being careless about fh_len too, in fh_to_dentry() and/or fh_to_parent(), and could oops in the same way: add the missing fh_len checks to those. Reported-by: Sasha Levin <levinsasha928@gmail.com> Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Sage Weil <sage@inktank.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13mempolicy: fix a memory corruption by refcount imbalance in alloc_pages_vma()Mel Gorman
commit 00442ad04a5eac08a98255697c510e708f6082e2 upstream. Commit cc9a6c877661 ("cpuset: mm: reduce large amounts of memory barrier related damage v3") introduced a potential memory corruption. shmem_alloc_page() uses a pseudo vma and it has one significant unique combination, vma->vm_ops=NULL and vma->policy->flags & MPOL_F_SHARED. get_vma_policy() does NOT increase a policy ref when vma->vm_ops=NULL and mpol_cond_put() DOES decrease a policy ref when a policy has MPOL_F_SHARED. Therefore, when a cpuset update race occurs, alloc_pages_vma() falls in 'goto retry_cpuset' path, decrements the reference count and frees the policy prematurely. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13mempolicy: fix refcount leak in mpol_set_shared_policy()KOSAKI Motohiro
commit 63f74ca21f1fad36d075e063f06dcc6d39fe86b2 upstream. When shared_policy_replace() fails to allocate new->policy is not freed correctly by mpol_set_shared_policy(). The problem is that shared mempolicy code directly call kmem_cache_free() in multiple places where it is easy to make a mistake. This patch creates an sp_free wrapper function and uses it. The bug was introduced pre-git age (IOW, before 2.6.12-rc2). [mgorman@suse.de: Editted changelog] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13mempolicy: fix a race in shared_policy_replace()Mel Gorman
commit b22d127a39ddd10d93deee3d96e643657ad53a49 upstream. shared_policy_replace() use of sp_alloc() is unsafe. 1) sp_node cannot be dereferenced if sp->lock is not held and 2) another thread can modify sp_node between spin_unlock for allocating a new sp node and next spin_lock. The bug was introduced before 2.6.12-rc2. Kosaki's original patch for this problem was to allocate an sp node and policy within shared_policy_replace and initialise it when the lock is reacquired. I was not keen on this approach because it partially duplicates sp_alloc(). As the paths were sp->lock is taken are not that performance critical this patch converts sp->lock to sp->mutex so it can sleep when calling sp_alloc(). [kosaki.motohiro@jp.fujitsu.com: Original patch] Signed-off-by: Mel Gorman <mgorman@suse.de> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Reviewed-by: Christoph Lameter <cl@linux.com> Cc: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13mempolicy: remove mempolicy sharingKOSAKI Motohiro
commit 869833f2c5c6e4dd09a5378cfc665ffb4615e5d2 upstream. Dave Jones' system call fuzz testing tool "trinity" triggered the following bug error with slab debugging enabled ============================================================================= BUG numa_policy (Not tainted): Poison overwritten ----------------------------------------------------------------------------- INFO: 0xffff880146498250-0xffff880146498250. First byte 0x6a instead of 0x6b INFO: Allocated in mpol_new+0xa3/0x140 age=46310 cpu=6 pid=32154 __slab_alloc+0x3d3/0x445 kmem_cache_alloc+0x29d/0x2b0 mpol_new+0xa3/0x140 sys_mbind+0x142/0x620 system_call_fastpath+0x16/0x1b INFO: Freed in __mpol_put+0x27/0x30 age=46268 cpu=6 pid=32154 __slab_free+0x2e/0x1de kmem_cache_free+0x25a/0x260 __mpol_put+0x27/0x30 remove_vma+0x68/0x90 exit_mmap+0x118/0x140 mmput+0x73/0x110 exit_mm+0x108/0x130 do_exit+0x162/0xb90 do_group_exit+0x4f/0xc0 sys_exit_group+0x17/0x20 system_call_fastpath+0x16/0x1b INFO: Slab 0xffffea0005192600 objects=27 used=27 fp=0x (null) flags=0x20000000004080 INFO: Object 0xffff880146498250 @offset=592 fp=0xffff88014649b9d0 The problem is that the structure is being prematurely freed due to a reference count imbalance. In the following case mbind(addr, len) should replace the memory policies of both vma1 and vma2 and thus they will become to share the same mempolicy and the new mempolicy will have the MPOL_F_SHARED flag. +-------------------+-------------------+ | vma1 | vma2(shmem) | +-------------------+-------------------+ | | addr addr+len alloc_pages_vma() uses get_vma_policy() and mpol_cond_put() pair for maintaining the mempolicy reference count. The current rule is that get_vma_policy() only increments refcount for shmem VMA and mpol_conf_put() only decrements refcount if the policy has MPOL_F_SHARED. In above case, vma1 is not shmem vma and vma->policy has MPOL_F_SHARED! The reference count will be decreased even though was not increased whenever alloc_page_vma() is called. This has been broken since commit [52cd3b07: mempolicy: rework mempolicy Reference Counting] in 2008. There is another serious bug with the sharing of memory policies. Currently, mempolicy rebind logic (it is called from cpuset rebinding) ignores a refcount of mempolicy and override it forcibly. Thus, any mempolicy sharing may cause mempolicy corruption. The bug was introduced by commit [68860ec1: cpusets: automatic numa mempolicy rebinding]. Ideally, the shared policy handling would be rewritten to either properly handle COW of the policy structures or at least reference count MPOL_F_SHARED based exclusively on information within the policy. However, this patch takes the easier approach of disabling any policy sharing between VMAs. Each new range allocated with sp_alloc will allocate a new policy, set the reference count to 1 and drop the reference count of the old policy. This increases the memory footprint but is not expected to be a major problem as mbind() is unlikely to be used for fine-grained ranges. It is also inefficient because it means we allocate a new policy even in cases where mbind_range() could use the new_policy passed to it. However, it is more straight-forward and the change should be invisible to the user. [mgorman@suse.de: Edited changelog] Reported-by: Dave Jones <davej@redhat.com>, Cc: Christoph Lameter <cl@linux.com>, Reviewed-by: Christoph Lameter <cl@linux.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13revert "mm: mempolicy: Let vma_merge and vma_split handle vma->vm_policy ↵KOSAKI Motohiro
linkages" commit 8d34694c1abf29df1f3c7317936b7e3e2e308d9b upstream. Commit 05f144a0d5c2 ("mm: mempolicy: Let vma_merge and vma_split handle vma->vm_policy linkages") removed vma->vm_policy updates code but it is the purpose of mbind_range(). Now, mbind_range() is virtually a no-op and while it does not allow memory corruption it is not the right fix. This patch is a revert. [mgorman@suse.de: Edited changelog] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Christoph Lameter <cl@linux.com> Cc: Josh Boyer <jwboyer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13mm: fix invalidate_complete_page2() lock orderingHugh Dickins
commit ec4d9f626d5908b6052c2973f37992f1db52e967 upstream. In fuzzing with trinity, lockdep protested "possible irq lock inversion dependency detected" when isolate_lru_page() reenabled interrupts while still holding the supposedly irq-safe tree_lock: invalidate_inode_pages2 invalidate_complete_page2 spin_lock_irq(&mapping->tree_lock) clear_page_mlock isolate_lru_page spin_unlock_irq(&zone->lru_lock) isolate_lru_page() is correct to enable interrupts unconditionally: invalidate_complete_page2() is incorrect to call clear_page_mlock() while holding tree_lock, which is supposed to nest inside lru_lock. Both truncate_complete_page() and invalidate_complete_page() call clear_page_mlock() before taking tree_lock to remove page from radix_tree. I guess invalidate_complete_page2() preferred to test PageDirty (again) under tree_lock before committing to the munlock; but since the page has already been unmapped, its state is already somewhat inconsistent, and no worse if clear_page_mlock() moved up. Reported-by: Sasha Levin <levinsasha928@gmail.com> Deciphered-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michel Lespinasse <walken@google.com> Cc: Ying Han <yinghan@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13hugetlb: do not use vma_hugecache_offset() for vma_prio_tree_foreachMichal Hocko
commit 36e4f20af833d1ce196e6a4ade05dc26c44652d1 upstream. Commit 0c176d52b0b2 ("mm: hugetlb: fix pgoff computation when unmapping page from vma") fixed pgoff calculation but it has replaced it by vma_hugecache_offset() which is not approapriate for offsets used for vma_prio_tree_foreach() because that one expects index in page units rather than in huge_page_shift. Johannes said: : The resulting index may not be too big, but it can be too small: assume : hpage size of 2M and the address to unmap to be 0x200000. This is regular : page index 512 and hpage index 1. If you have a VMA that maps the file : only starting at the second huge page, that VMAs vm_pgoff will be 512 but : you ask for offset 1 and miss it even though it does map the page of : interest. hugetlb_cow() will try to unmap, miss the vma, and retry the : cow until the allocation succeeds or the skipped vma(s) go away. Signed-off-by: Michal Hocko <mhocko@suse.cz> Acked-by: Hillf Danton <dhillf@gmail.com> Cc: Mel Gorman <mel@csn.ul.ie> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: David Rientjes <rientjes@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-10-13slab: fix the DEADLOCK issue on l3 alien lockMichael Wang
commit 947ca1856a7e60aa6d20536785e6a42dff25aa6e upstream. DEADLOCK will be report while running a kernel with NUMA and LOCKDEP enabled, the process of this fake report is: kmem_cache_free() //free obj in cachep -> cache_free_alien() //acquire cachep's l3 alien lock -> __drain_alien_cache() -> free_block() -> slab_destroy() -> kmem_cache_free() //free slab in cachep->slabp_cache -> cache_free_alien() //acquire cachep->slabp_cache's l3 alien lock Since the cachep and cachep->slabp_cache's l3 alien are in the same lock class, fake report generated. This should not happen since we already have init_lock_keys() which will reassign the lock class for both l3 list and l3 alien. However, init_lock_keys() was invoked at a wrong position which is before we invoke enable_cpucache() on each cache. Since until set slab_state to be FULL, we won't invoke enable_cpucache() on caches to build their l3 alien while creating them, so although we invoked init_lock_keys(), the l3 alien lock class won't change since we don't have them until invoked enable_cpucache() later. This patch will invoke init_lock_keys() after we done enable_cpucache() instead of before to avoid the fake DEADLOCK report. Michael traced the problem back to a commit in release 3.0.0: commit 30765b92ada267c5395fc788623cb15233276f5c Author: Peter Zijlstra <peterz@infradead.org> Date: Thu Jul 28 23:22:56 2011 +0200 slab, lockdep: Annotate the locks before using them Fernando found we hit the regular OFF_SLAB 'recursion' before we annotate the locks, cure this. The relevant portion of the stack-trace: > [ 0.000000] [<c085e24f>] rt_spin_lock+0x50/0x56 > [ 0.000000] [<c04fb406>] __cache_free+0x43/0xc3 > [ 0.000000] [<c04fb23f>] kmem_cache_free+0x6c/0xdc > [ 0.000000] [<c04fb2fe>] slab_destroy+0x4f/0x53 > [ 0.000000] [<c04fb396>] free_block+0x94/0xc1 > [ 0.000000] [<c04fc551>] do_tune_cpucache+0x10b/0x2bb > [ 0.000000] [<c04fc8dc>] enable_cpucache+0x7b/0xa7 > [ 0.000000] [<c0bd9d3c>] kmem_cache_init_late+0x1f/0x61 > [ 0.000000] [<c0bba687>] start_kernel+0x24c/0x363 > [ 0.000000] [<c0bba0ba>] i386_start_kernel+0xa9/0xaf Reported-by: Fernando Lopez-Lezcano <nando@ccrma.Stanford.EDU> Acked-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1311888176.2617.379.camel@laptop Signed-off-by: Ingo Molnar <mingo@elte.hu> The commit moved init_lock_keys() before we build up the alien, so we failed to reclass it. Acked-by: Christoph Lameter <cl@linux.com> Tested-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Michael Wang <wangyun@linux.vnet.ibm.com> Signed-off-by: Pekka Enberg <penberg@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-28thp: avoid VM_BUG_ON page_count(page) false positives in ↵Andrea Arcangeli
__collapse_huge_page_copy Speculative cache pagecache lookups can elevate the refcount from under us, so avoid the false positive. If the refcount is < 2 we'll be notified by a VM_BUG_ON in put_page_testzero as there are two put_page(src_page) in a row before returning from this function. Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Hugh Dickins <hughd@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Petr Holasek <pholasek@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-17memory hotplug: fix section info double registration bugqiuxishi
There may be a bug when registering section info. For example, on my Itanium platform, the pfn range of node0 includes the other nodes, so other nodes' section info will be double registered, and memmap's page count will equal to 3. node0: start_pfn=0x100, spanned_pfn=0x20fb00, present_pfn=0x7f8a3, => 0x000100-0x20fc00 node1: start_pfn=0x80000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x080000-0x100000 node2: start_pfn=0x100000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x100000-0x180000 node3: start_pfn=0x180000, spanned_pfn=0x80000, present_pfn=0x80000, => 0x180000-0x200000 free_all_bootmem_node() register_page_bootmem_info_node() register_page_bootmem_info_section() When hot remove memory, we can't free the memmap's page because page_count() is 2 after put_page_bootmem(). sparse_remove_one_section() free_section_usemap() free_map_bootmem() put_page_bootmem() [akpm@linux-foundation.org: add code comment] Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Signed-off-by: Jiang Liu <jiang.liu@huawei.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-17mm/page_alloc: fix the page address of higher page's buddy calculationLi Haifeng
The heuristic method for buddy has been introduced since commit 43506fad21ca ("mm/page_alloc.c: simplify calculation of combined index of adjacent buddy lists"). But the page address of higher page's buddy was wrongly calculated, which will lead page_is_buddy to fail for ever. IOW, the heuristic method would be disabled with the wrong page address of higher page's buddy. Calculating the page address of higher page's buddy should be based higher_page with the offset between index of higher page and index of higher page's buddy. Signed-off-by: Haifeng Li <omycle@gmail.com> Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Reviewed-by: Michal Hocko <mhocko@suse.cz> Cc: KyongHo Cho <pullip.cho@samsung.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Minchan Kim <minchan.kim@gmail.com> Cc: Johannes Weiner <jweiner@redhat.com> Cc: <stable@vger.kernel.org> [2.6.38+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-17slub: consider pfmemalloc_match() in get_partial_node()Joonsoo Kim
get_partial() is currently not checking pfmemalloc_match() meaning that it is possible for pfmemalloc pages to leak to non-pfmemalloc users. This is a problem in the following situation. Assume that there is a request from normal allocation and there are no objects in the per-cpu cache and no node-partial slab. In this case, slab_alloc enters the slow path and new_slab_objects() is called which may return a PFMEMALLOC page. As the current user is not allowed to access PFMEMALLOC page, deactivate_slab() is called ([5091b74a: mm: slub: optimise the SLUB fast path to avoid pfmemalloc checks]) and returns an object from PFMEMALLOC page. Next time, when we get another request from normal allocation, slab_alloc() enters the slow-path and calls new_slab_objects(). In new_slab_objects(), we call get_partial() and get a partial slab which was just deactivated but is a pfmemalloc page. We extract one object from it and re-deactivate. "deactivate -> re-get in get_partial -> re-deactivate" occures repeatedly. As a result, access to PFMEMALLOC page is not properly restricted and it can cause a performance degradation due to frequent deactivation. deactivation frequently. This patch changes get_partial_node() to take pfmemalloc_match() into account and prevents the "deactivate -> re-get in get_partial() scenario. Instead, new_slab() is called. Signed-off-by: Joonsoo Kim <js1304@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-17slab: fix starting index for finding another objectJoonsoo Kim
In array cache, there is a object at index 0, check it. Signed-off-by: Joonsoo Kim <js1304@gmail.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-17slab: do ClearSlabPfmemalloc() for all pages of slabMel Gorman
Right now, we call ClearSlabPfmemalloc() for first page of slab when we clear SlabPfmemalloc flag. This is fine for most swap-over-network use cases as it is expected that order-0 pages are in use. Unfortunately it is possible that that __ac_put_obj() checks SlabPfmemalloc on a tail page and while this is harmless, it is sloppy. This patch ensures that the head page is always used. This problem was originally identified by Joonsoo Kim. [js1304@gmail.com: Original implementation and problem identification] Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Joonsoo Kim <js1304@gmail.com> Cc: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-17memory hotplug: reset pgdat->kswapd to NULL if creating kernel thread failsWen Congyang
If kthread_run() fails, pgdat->kswapd contains errno. When we stop this thread, we only check whether pgdat->kswapd is NULL and access it. If it contains errno, it will cause page fault. Reset pgdat->kswapd to NULL when creating kernel thread fails can avoid this problem. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-14Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull a core sparse warning fix from Ingo Molnar * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: mm/memblock: Use NULL instead of 0 for pointers
2012-09-06Remove user-triggerable BUG from mpol_to_strDave Jones
Trivially triggerable, found by trinity: kernel BUG at mm/mempolicy.c:2546! Process trinity-child2 (pid: 23988, threadinfo ffff88010197e000, task ffff88007821a670) Call Trace: show_numa_map+0xd5/0x450 show_pid_numa_map+0x13/0x20 traverse+0xf2/0x230 seq_read+0x34b/0x3e0 vfs_read+0xac/0x180 sys_pread64+0xa2/0xc0 system_call_fastpath+0x1a/0x1f RIP: mpol_to_str+0x156/0x360 Cc: stable@vger.kernel.org Signed-off-by: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-09-05mm/memblock: Use NULL instead of 0 for pointersSachin Kamat
This type cleanup also fixes the following sparse warning: mm/memblock.c:249:49: warning: Using plain integer as NULL pointer Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org> Acked-by: Tejun Heo <tj@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: patches@linaro.org Cc: linux-mm@kvack.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-29mm, slab: lock the correct nodelist after reenabling irqsDavid Rientjes
cache_grow() can reenable irqs so the cpu (and node) can change, so ensure that we take list_lock on the correct nodelist. This fixes an issue with commit 072bb0aa5e06 ("mm: sl[au]b: add knowledge of PFMEMALLOC reserve pages") where list_lock for the wrong node was taken after growing the cache. Reported-and-tested-by: Haggai Eran <haggaie@mellanox.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-25Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull block-related fixes from Jens Axboe: - Improvements to the buffered and direct write IO plugging from Fengguang. - Abstract out the mapping of a bio in a request, and use that to provide a blk_bio_map_sg() helper. Useful for mapping just a bio instead of a full request. - Regression fix from Hugh, fixing up a patch that went into the previous release cycle (and marked stable, too) attempting to prevent a loop in __getblk_slow(). - Updates to discard requests, fixing up the sizing and how we align them. Also a change to disallow merging of discard requests, since that doesn't really work properly yet. - A few drbd fixes. - Documentation updates. * 'for-linus' of git://git.kernel.dk/linux-block: block: replace __getblk_slow misfix by grow_dev_page fix drbd: Write all pages of the bitmap after an online resize drbd: Finish requests that completed while IO was frozen drbd: fix drbd wire compatibility for empty flushes Documentation: update tunable options in block/cfq-iosched.txt Documentation: update tunable options in block/cfq-iosched.txt Documentation: update missing index files in block/00-INDEX block: move down direct IO plugging block: remove plugging at buffered write time block: disable discard request merge temporarily bio: Fix potential memory leak in bio_find_or_create_slab() block: Don't use static to define "void *p" in show_partition_start() block: Add blk_bio_map_sg() helper block: Introduce __blk_segment_map_sg() helper fs/block-dev.c:fix performance regression in O_DIRECT writes to md block devices block: split discard into aligned requests block: reorganize rounding of max_discard_sectors
2012-08-23Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "This tree contains misc fixlets: a perf script python binding fix, a uprobes fix and a syscall tracing fix." * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf tools: Add missing files to build the python binding uprobes: Fix mmap_region()'s mm->mm_rb corruption if uprobe_mmap() fails tracing/syscalls: Fix perf syscall tracing when syscall_nr == -1
2012-08-21mm: compaction: Abort async compaction if locks are contended or taking too longMel Gorman
Jim Schutt reported a problem that pointed at compaction contending heavily on locks. The workload is straight-forward and in his own words; The systems in question have 24 SAS drives spread across 3 HBAs, running 24 Ceph OSD instances, one per drive. FWIW these servers are dual-socket Intel 5675 Xeons w/48 GB memory. I've got ~160 Ceph Linux clients doing dd simultaneously to a Ceph file system backed by 12 of these servers. Early in the test everything looks fine procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu------- r b swpd free buff cache si so bi bo in cs us sy id wa st 31 15 0 287216 576 38606628 0 0 2 1158 2 14 1 3 95 0 0 27 15 0 225288 576 38583384 0 0 18 2222016 203357 134876 11 56 17 15 0 28 17 0 219256 576 38544736 0 0 11 2305932 203141 146296 11 49 23 17 0 6 18 0 215596 576 38552872 0 0 7 2363207 215264 166502 12 45 22 20 0 22 18 0 226984 576 38596404 0 0 3 2445741 223114 179527 12 43 23 22 0 and then it goes to pot procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu------- r b swpd free buff cache si so bi bo in cs us sy id wa st 163 8 0 464308 576 36791368 0 0 11 22210 866 536 3 13 79 4 0 207 14 0 917752 576 36181928 0 0 712 1345376 134598 47367 7 90 1 2 0 123 12 0 685516 576 36296148 0 0 429 1386615 158494 60077 8 84 5 3 0 123 12 0 598572 576 36333728 0 0 1107 1233281 147542 62351 7 84 5 4 0 622 7 0 660768 576 36118264 0 0 557 1345548 151394 59353 7 85 4 3 0 223 11 0 283960 576 36463868 0 0 46 1107160 121846 33006 6 93 1 1 0 Note that system CPU usage is very high blocks being written out has dropped by 42%. He analysed this with perf and found perf record -g -a sleep 10 perf report --sort symbol --call-graph fractal,5 34.63% [k] _raw_spin_lock_irqsave | |--97.30%-- isolate_freepages | compaction_alloc | unmap_and_move | migrate_pages | compact_zone | compact_zone_order | try_to_compact_pages | __alloc_pages_direct_compact | __alloc_pages_slowpath | __alloc_pages_nodemask | alloc_pages_vma | do_huge_pmd_anonymous_page | handle_mm_fault | do_page_fault | page_fault | | | |--87.39%-- skb_copy_datagram_iovec | | tcp_recvmsg | | inet_recvmsg | | sock_recvmsg | | sys_recvfrom | | system_call | | __recv | | | | | --100.00%-- (nil) | | | --12.61%-- memcpy --2.70%-- [...] There was other data but primarily it is all showing that compaction is contended heavily on the zone->lock and zone->lru_lock. commit [b2eef8c0: mm: compaction: minimise the time IRQs are disabled while isolating pages for migration] noted that it was possible for migration to hold the lru_lock for an excessive amount of time. Very broadly speaking this patch expands the concept. This patch introduces compact_checklock_irqsave() to check if a lock is contended or the process needs to be scheduled. If either condition is true then async compaction is aborted and the caller is informed. The page allocator will fail a THP allocation if compaction failed due to contention. This patch also introduces compact_trylock_irqsave() which will acquire the lock only if it is not contended and the process does not need to schedule. Reported-by: Jim Schutt <jaschut@sandia.gov> Tested-by: Jim Schutt <jaschut@sandia.gov> Signed-off-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21mm: have order > 0 compaction start near a pageblock with free pagesMel Gorman
Commit 7db8889ab05b ("mm: have order > 0 compaction start off where it left") introduced a caching mechanism to reduce the amount work the free page scanner does in compaction. However, it has a problem. Consider two process simultaneously scanning free pages C Process A M S F |---------------------------------------| Process B M FS C is zone->compact_cached_free_pfn S is cc->start_pfree_pfn M is cc->migrate_pfn F is cc->free_pfn In this diagram, Process A has just reached its migrate scanner, wrapped around and updated compact_cached_free_pfn accordingly. Simultaneously, Process B finishes isolating in a block and updates compact_cached_free_pfn again to the location of its free scanner. Process A moves to "end_of_zone - one_pageblock" and runs this check if (cc->order > 0 && (!cc->wrapped || zone->compact_cached_free_pfn > cc->start_free_pfn)) pfn = min(pfn, zone->compact_cached_free_pfn); compact_cached_free_pfn is above where it started so the free scanner skips almost the entire space it should have scanned. When there are multiple processes compacting it can end in a situation where the entire zone is not being scanned at all. Further, it is possible for two processes to ping-pong update to compact_cached_free_pfn which is just random. Overall, the end result wrecks allocation success rates. There is not an obvious way around this problem without introducing new locking and state so this patch takes a different approach. First, it gets rid of the skip logic because it's not clear that it matters if two free scanners happen to be in the same block but with racing updates it's too easy for it to skip over blocks it should not. Second, it updates compact_cached_free_pfn in a more limited set of circumstances. If a scanner has wrapped, it updates compact_cached_free_pfn to the end of the zone. When a wrapped scanner isolates a page, it updates compact_cached_free_pfn to point to the highest pageblock it can isolate pages from. If a scanner has not wrapped when it has finished isolated pages it checks if compact_cached_free_pfn is pointing to the end of the zone. If so, the value is updated to point to the highest pageblock that pages were isolated from. This value will not be updated again until a free page scanner wraps and resets compact_cached_free_pfn. This is not optimal and it can still race but the compact_cached_free_pfn will be pointing to or very near a pageblock with free pages. Signed-off-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21mm: correct page->pfmemalloc to fix deactivate_slab regressionAlex Shi
Commit cfd19c5a9ecf ("mm: only set page->pfmemalloc when ALLOC_NO_WATERMARKS was used") tried to narrow down page->pfmemalloc setting, but it missed some places the pfmemalloc should be set. So, in __slab_alloc, the unalignment pfmemalloc and ALLOC_NO_WATERMARKS cause incorrect deactivate_slab() on our core2 server: 64.73% fio [kernel.kallsyms] [k] _raw_spin_lock | --- _raw_spin_lock | |---0.34%-- deactivate_slab | __slab_alloc | kmem_cache_alloc | | That causes our fio sync write performance to have a 40% regression. Move the checking in get_page_from_freelist() which resolves this issue. Signed-off-by: Alex Shi <alex.shi@intel.com> Acked-by: Mel Gorman <mgorman@suse.de> Cc: David Miller <davem@davemloft.net Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Tested-by: Eric Dumazet <eric.dumazet@gmail.com> Tested-by: Sage Weil <sage@inktank.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21mm/compaction.c: fix deferring compaction mistakeMinchan Kim
Commit aff622495c9a ("vmscan: only defer compaction for failed order and higher") fixed bad deferring policy but made mistake about checking compact_order_failed in __compact_pgdat(). So it can't update compact_order_failed with the new order. This ends up preventing correct operation of policy deferral. This patch fixes it. Signed-off-by: Minchan Kim <minchan@kernel.org> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: Mel Gorman <mel@csn.ul.ie> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21mm: change nr_ptes BUG_ON to WARN_ONHugh Dickins
Occasionally an isolated BUG_ON(mm->nr_ptes) gets reported, indicating that not all the page tables allocated could be found and freed when exit_mmap() tore down the user address space. There's usually nothing we can say about it, beyond that it's probably a sign of some bad memory or memory corruption; though it might still indicate a bug in vma or page table management (and did recently reveal a race in THP, fixed a few months ago). But one overdue change we can make is from BUG_ON to WARN_ON. It's fairly likely that the system will crash shortly afterwards in some other way (for example, the BUG_ON(page_mapped(page)) in __delete_from_page_cache(), once an inode mapped into the lost page tables gets evicted); but might tell us more before that. Change the BUG_ON(page_mapped) to WARN_ON too? Later perhaps: I'm less eager, since that one has several times led to fixes. Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-21uprobes: Fix mmap_region()'s mm->mm_rb corruption if uprobe_mmap() failsOleg Nesterov
This patch fixes: https://bugzilla.redhat.com/show_bug.cgi?id=843640 If mmap_region()->uprobe_mmap() fails, unmap_and_free_vma path does unmap_region() but does not remove the soon-to-be-freed vma from rb tree. Actually there are more problems but this is how William noticed this bug. Perhaps we could do do_munmap() + return in this case, but in fact it is simply wrong to abort if uprobe_mmap() fails. Until at least we move the !UPROBE_COPY_INSN code from install_breakpoint() to uprobe_register(). For example, uprobe_mmap()->install_breakpoint() can fail if the probed insn is not supported (remember, uprobe_register() succeeds if nobody mmaps inode/offset), mmap() should not fail in this case. dup_mmap()->uprobe_mmap() is wrong too by the same reason, fork() can race with uprobe_register() and fail for no reason if it wins the race and does install_breakpoint() first. And, if nothing else, both mmap_region() and dup_mmap() return success if uprobe_mmap() fails. Change them to ignore the error code from uprobe_mmap(). Reported-and-tested-by: William Cohen <wcohen@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> # v3.5 Cc: Anton Arapov <anton@redhat.com> Cc: William Cohen <wcohen@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20120819171042.GB26957@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-08-09block: move down direct IO pluggingFengguang Wu
Move unplugging for direct I/O from around ->direct_IO() down to do_blockdev_direct_IO(). This implicitly adds plugging for direct writes. CC: Li Shaohua <shli@fusionio.com> Acked-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-08-09block: remove plugging at buffered write timeFengguang Wu
Buffered write(2) is not directly tied to IO, so it's not suitable to handle plug in generic_file_aio_write(). Note that plugging for O_SYNC writes is also removed. The user may pass arbitrary @size arguments, which may be much larger than the preferable I/O size, or may cross extent/device boundaries. Let the lower layers handle the plugging. The plugging code here actually turns them into no-ops. CC: Li Shaohua <shli@fusionio.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-08-04vfs: kill write_super and sync_supersArtem Bityutskiy
Finally we can kill the 'sync_supers' kernel thread along with the '->write_super()' superblock operation because all the users are gone. Now every file-system is supposed to self-manage own superblock and its dirty state. The nice thing about killing this thread is that it improves power management. Indeed, 'sync_supers' is a source of monotonic system wake-ups - it woke up every 5 seconds no matter what - even if there were no dirty superblocks and even if there were no file-systems using this service (e.g., btrfs and journalled ext4 do not need it). So it was wasting power most of the time. And because the thread was in the core of the kernel, all systems had to have it. So I am quite happy to make it go away. Interestingly, this thread is a left-over from the pdflush kernel thread which was a self-forking kernel thread responsible for all the write-back in old Linux kernels. It was turned into per-block device BDI threads, and 'sync_supers' was a left-over. Thus, R.I.P, pdflush as well. Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-08-02mm: remove node_start_pfn checking in new WARN_ON for nowLinus Torvalds
Borislav Petkov reports that the new warning added in commit 88fdf75d1bb5 ("mm: warn if pg_data_t isn't initialized with zero") triggers for him, and it is the node_start_pfn field that has already been initialized once. The call trace looks like this: x86_64_start_kernel -> x86_64_start_reservations -> start_kernel -> setup_arch -> paging_init -> zone_sizes_init -> free_area_init_nodes -> free_area_init_node and (with the warning replaced by debug output), Borislav sees On node 0 totalpages: 4193848 DMA zone: 64 pages used for memmap DMA zone: 6 pages reserved DMA zone: 3890 pages, LIFO batch:0 DMA32 zone: 16320 pages used for memmap DMA32 zone: 798464 pages, LIFO batch:31 Normal zone: 52736 pages used for memmap Normal zone: 3322368 pages, LIFO batch:31 free_area_init_node: pgdat->node_start_pfn: 4423680 <---- On node 1 totalpages: 4194304 Normal zone: 65536 pages used for memmap Normal zone: 4128768 pages, LIFO batch:31 free_area_init_node: pgdat->node_start_pfn: 8617984 <---- On node 2 totalpages: 4194304 Normal zone: 65536 pages used for memmap Normal zone: 4128768 pages, LIFO batch:31 free_area_init_node: pgdat->node_start_pfn: 12812288 <---- On node 3 totalpages: 4194304 Normal zone: 65536 pages used for memmap Normal zone: 4128768 pages, LIFO batch:31 so remove the bogus warning for now to avoid annoying people. Minchan Kim is looking at it. Reported-by: Borislav Petkov <bp@amd64.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-08-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull second vfs pile from Al Viro: "The stuff in there: fsfreeze deadlock fixes by Jan (essentially, the deadlock reproduced by xfstests 068), symlink and hardlink restriction patches, plus assorted cleanups and fixes. Note that another fsfreeze deadlock (emergency thaw one) is *not* dealt with - the series by Fernando conflicts a lot with Jan's, breaks userland ABI (FIFREEZE semantics gets changed) and trades the deadlock for massive vfsmount leak; this is going to be handled next cycle. There probably will be another pull request, but that stuff won't be in it." Fix up trivial conflicts due to unrelated changes next to each other in drivers/{staging/gdm72xx/usb_boot.c, usb/gadget/storage_common.c} * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (54 commits) delousing target_core_file a bit Documentation: Correct s_umount state for freeze_fs/unfreeze_fs fs: Remove old freezing mechanism ext2: Implement freezing btrfs: Convert to new freezing mechanism nilfs2: Convert to new freezing mechanism ntfs: Convert to new freezing mechanism fuse: Convert to new freezing mechanism gfs2: Convert to new freezing mechanism ocfs2: Convert to new freezing mechanism xfs: Convert to new freezing code ext4: Convert to new freezing mechanism fs: Protect write paths by sb_start_write - sb_end_write fs: Skip atime update on frozen filesystem fs: Add freezing handling to mnt_want_write() / mnt_drop_write() fs: Improve filesystem freezing handling switch the protection of percpu_counter list to spinlock nfsd: Push mnt_want_write() outside of i_mutex btrfs: Push mnt_want_write() outside of i_mutex fat: Push mnt_want_write() outside of i_mutex ...
2012-08-01Merge branch 'for-3.6/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull core block IO bits from Jens Axboe: "The most complicated part if this is the request allocation rework by Tejun, which has been queued up for a long time and has been in for-next ditto as well. There are a few commits from yesterday and today, mostly trivial and obvious fixes. So I'm pretty confident that it is sound. It's also smaller than usual." * 'for-3.6/core' of git://git.kernel.dk/linux-block: block: remove dead func declaration block: add partition resize function to blkpg ioctl block: uninitialized ioc->nr_tasks triggers WARN_ON block: do not artificially constrain max_sectors for stacking drivers blkcg: implement per-blkg request allocation block: prepare for multiple request_lists block: add q->nr_rqs[] and move q->rq.elvpriv to q->nr_rqs_elvpriv blkcg: inline bio_blkcg() and friends block: allocate io_context upfront block: refactor get_request[_wait]() block: drop custom queue draining used by scsi_transport_{iscsi|fc} mempool: add @gfp_mask to mempool_create_node() blkcg: make root blkcg allocation use %GFP_KERNEL blkcg: __blkg_lookup_create() doesn't need radix preload
2012-07-31Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds
Merge Andrew's second set of patches: - MM - a few random fixes - a couple of RTC leftovers * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (120 commits) rtc/rtc-88pm80x: remove unneed devm_kfree rtc/rtc-88pm80x: assign ret only when rtc_register_driver fails mm: hugetlbfs: close race during teardown of hugetlbfs shared page tables tmpfs: distribute interleave better across nodes mm: remove redundant initialization mm: warn if pg_data_t isn't initialized with zero mips: zero out pg_data_t when it's allocated memcg: gix memory accounting scalability in shrink_page_list mm/sparse: remove index_init_lock mm/sparse: more checks on mem_section number mm/sparse: optimize sparse_index_alloc memcg: add mem_cgroup_from_css() helper memcg: further prevent OOM with too many dirty pages memcg: prevent OOM with too many dirty pages mm: mmu_notifier: fix freed page still mapped in secondary MMU mm: memcg: only check anon swapin page charges for swap cache mm: memcg: only check swap cache pages for repeat